System and method for picking items

ABSTRACT

A system and method for picking items is disclosed. The system includes a grid-based storage area and an order assembly area. The system includes an array of presentation positions, the presentation positions being configured and adapted so as to present storage containers delivered to the presentation positions so as to enable picking of items contained therein.

The present invention relates to a system and method for picking itemsfrom a storage system. More specifically but not exclusively, it relatesto a system and method for picking items to fulfil customer orders in anonline retailing environment, said order picking system comprising itempresentation systems and devices.

Some commercial and industrial activities require systems that enablethe storage and retrieval of a large number of different stock items.

In one known form of fulfilment centre, as shown in FIG. 1, fulfilmentsystems referred to as ‘zone pick’ or ‘pick and pass’ are used. In suchsystems, items and stock required to fulfil customer orders are locatedin storage bins or containers, the storage bins or containers beingarranged along aisles. On the opposite side of the aisle from thestorage bins or containers, a conveyor system is located, the conveyorsystem carrying customer delivery bins or containers. The conveyorsystem is arranged so as to pass a proportion of the delivery bins orcontainers moving on the backline conveyor through pick stations, viastation conveyors, where items ordered by a customer are transferred byan operative from a storage bin or container to a customer delivery binor container. When a customer delivery container is located at a pickingstation on the conveyor system, it is paused and an operator selects arequired item from a storage bin or container and places it in thecustomer delivery bin or container.

It will be appreciated that in certain market sectors such as onlinegrocery retailing, this known form of operation may require many pickaisles, many pick stations and many operators to fulfil customer ordersand hence requires a large initial expenditure. Furthermore, expansionof such systems is difficult as the infrastructure design and locationis fixed from the outset.

In a further known type of system for the storage and retrieval of itemsof multiple product lines, the items are again located in storage binsor containers. However, in the alternative known system the bins orcontainers are arranged in stacks on top of one another, the stacksbeing arranged in rows. The storage bins or containers are accessed fromabove and removed from the stacks by load handling devices.

EP 3030504 B1 (Ocado Innovation Limited) the content of which isincorporated herein by reference, describes a robotic picking system inwhich stacks of containers are arranged within a frame structure. Asystem of this type is illustrated schematically in FIGS. 5 and 6 of theaccompanying drawings. The robotic load handling devices arecontrollably moved around on a system of tracks, the tracks forming agrid located above the stacks of containers. In the robotic pickingsystem described in EP3030504 B1, the grid comprises a series of gridspaces defined by the tracks, each stack of containers being locatedwithin the footprint of a single grid space. In use, the robotic loadhandlers run on the tracks above the stacks and are controllablypositioned above a predetermined stack of containers. Once in position,a lifting mechanism is lowered, a part of which, a gripper device,engages with a container and lifts said bin or container from the stackin to a cavity within the load handling device. In this particularsystem the cross-section of the robotic load handling devicesubstantially conforms to the area of a single grid space. Furthermore,the tracks and robotic load handling devices are configured such thattwo load handling devices may occupy adjacent grid spaces and pass eachother in either direction when in operation.

Other forms of robotic load handling device are described in, forexample, Norwegian patent number NO 317366 B1 (Autostore AS), thecontent of which is incorporated herein by reference, in whichcantilever-type load handling devices disclosed occupy two grid spaceswhen in operation. It will be appreciated that in the context of theinvention described in more detail below with reference to the specificembodiments any form or configuration of load handling device may beused in place of the two examples described above.

Such storage systems remove the need for aisles between the storage andpicking areas and also allow a higher density of storage of products oritems in the fulfilment centre for a given volume.

In the known, grid-based, robotic picking systems described above, thestorage bin or container being lifted from a stack may contain inventoryitems needed to fulfil a customer order. Once lifted by the loadhandling device, the storage bin or container is delivered by the loadhandling device to an output port above or adjacent a pick station or tothe pick station per se. At the pick station, the required inventoryitem or items may be manually or robotically removed from the storagebin or container and placed in a delivery container, the deliverycontainer forming part of the customer order, and being filled fordispatch at the appropriate time.

It will be appreciated that such an order may comprise a plurality ofdelivery containers, the number of delivery containers required beingdefined by the number of items or products ordered. Accordingly, a largenumber of containers or bins may need to be moved from storage positionswithin stacks to the pick stations.

Advantageously, the modular nature of grid-based picking systems enablesan overall picking and storage system to be built in stages and expandedas required, thereby spreading out capital expenditure and costs asnecessary.

However, it will be appreciated that moving storage bins or containersto a pick station and subsequently picking inventory items from saidstorage bins or containers, whether manually or robotically, in todelivery bins or containers can sometimes be delayed. Such delays atpick stations may cause load handling device congestion at the outputports of the system or at the pick stations and can cause delays in theassembly and hence dispatch of customer orders.

This is a disadvantage of such systems that each inventory item must bedelivered in a storage bin or container to a pick station as required,there is no ability to keep frequently required items at the pickstations.

Additionally, the number of pick stations in a grid-based system islimited by the space available for the footprint of the pick stations.As a result of this, frequently required items and products need to betransported many times by the robotic load handlers, thereby increasingthe load handler movements required and further congestion at outputports.

Furthermore, such grid-based systems require all inventory items to beplaced in to storage bins or containers in order to be available topick. This limits the systems to inventory items that can be placed incontainers or bins and requires an additional unpacking step to beperformed as part of the picking system or method.

It will be appreciated that both the types of known storage and pickingsystems described above, are operated under the control of computerutilities acting so as to control the movement and location of storagebins or containers and delivery containers, the movement and location ofstock, and the location and number of operatives required at any givenpoint in the system. Additionally, in a grid-based system the computerutilities control the movement and location of the load handling devicesand may control the communication between the load handling devices andthe order picking system.

Given the known systems described above, especially where labour isrelatively inexpensive and where there is a concentration of frequentlyordered or “fast moving” items, it may be beneficial to combine agrid-based storage and picking system with a conventional ‘zone pick’ or‘pick and pass’ conveyor based picking system.

According to the invention there is provided a system for picking itemsfrom storage, the system comprising a grid-based storage system, thestorage system comprising a series of storage containers, the storagecontainers comprising items to be stored, the storage containers beinglocated in stacks within a framework, in which a portion of theframework comprises an output column, said output column being providedwith a plurality of presentation positions, the storage containers beingmovable from storage positions within the stacks to said presentationpositions remote from the stacks via the output column, saidpresentation positions being arranged so as locate a plurality ofstorage containers on at least one face of the storage system, thepresentation positions being arranged such that the items stored in saidstorage containers are accessible to an item picker.

According to the invention there is further provided a method of pickingitems from a storage system using such a picking system.

In this way, the present invention overcomes the problems of the priorart and provides a system and method of increasing the speed at whichcustomer orders can be compiled whilst reducing the overall cost andimproving the efficiency of customer fulfilment centres or otherindustrial scenarios where items are stored and access to said items isregularly required.

The invention will now be described with reference to the accompanyingdiagrammatic drawings in which:

FIG. 1 is a schematic, perspective view of one known form of ‘zone pick’or ‘pick and pass’ picking system, showing a pick aisle, a storage areaand two order assembly areas, the storage area further comprisingstorage bins or containers positioned so as to present a pick face to anoperative, the storage bins or containers comprising items, products orinventory awaiting assimilation in to customer orders;

FIG. 2 is a schematic, plan view of the system of FIG. 1 showing thestorage area, the pick face and an example of one order assembly area inmore detail, the pick aisle comprising a backline conveyor and portionsof station conveyor;

FIG. 3 is a schematic, cross-sectional view of the order assembly areaof FIG. 1, through the pick aisle in the region of the pick station;

FIG. 4 is a schematic, perspective view of a typical form of storagearea of the system of FIGS. 1 to 3;

FIG. 5 is a schematic, perspective view of one form of grid-basedrobotic picking system, the system comprising a grid located abovestacks of storage bins or bins, a series of tracks disposed on the grid,the tracks carrying load handling devices, the load handling devicesadapted to pick up containers or bins from the stacks beneath the grid;

FIG. 6 is a schematic perspective views of one form of known roboticload handling device for use with the grid-based storage area of thezone pick solution of FIG. 5;

FIG. 7a is a schematic, perspective view of an order picking system inaccordance with one form of the invention, the system comprising astorage area comprising a grid-based storage solution, the grid-basedsolution comprising a robotic picking system, the system housing aplurality of stacks of storage bins or containers in the storage area,the grid based system comprising an array of storage bin presentationpositions;

FIG. 7b is a schematic, side view of the order picking system of FIG. 7ain accordance with one form of the invention, the system comprising aplurality of load handling devices of the type shown in FIG. 6,installed on the frame structure of FIG. 5, together with at least onerobotic load handling device, the framework and the load handling devicetogether comprising the main components of a robotic storage and pickingsystem for storage and handling of items to be stored;

FIG. 7c is a schematic, side view of one form of the order pickingsystem of FIG. 7a in accordance with the invention, showing pre-pickpositions and presentation positions in the storage area, the systemfurther comprising one mechanism for transferring storage containers orbins from the pre-pick positions to the presentation positions, theorder assembly portion comprising a trolley pick system;

FIG. 8a is a schematic, perspective view of a part of the presentationportion of the storage system of the order picking system in accordancewith one form of the invention, in which containers from the grid-basedstorage system are delivered to the storage area by robotic loadhandling devices;

FIG. 8b is a schematic, side view of the presentation portion of FIG. 8ashowing a further form of mechanism for moving storage bins of bins fromdelivered locations to presentation positions;

FIG. 8c is a schematic, perspective view of the system of FIG. 8bshowing the mechanism for moving the storage containers in more detail;

FIG. 8d is a schematic, side view of a further form of storage area ofan order picking system in accordance with one form of the invention,the system comprising a bin lift device for transferring the storagecontainers or bins to the presentation positions;

FIG. 8e is a schematic, perspective view of a further form of thestorage area of the order picking system in accordance with one form ofthe invention, the storage area comprising a series of shuttle devicesoperable on a frame comprising a looped track for transferring thestorage containers or bins to the presentation positions;

FIG. 8f is a schematic, cutaway perspective view of the order pickingsystem of FIG. 8e , showing in more detail the shuttle devices of FIG.8e operable on the looped track;

FIG. 8g is a schematic, perspective view of a further form of thestorage area of the order picking system in accordance with one form ofthe invention, the storage area comprising a series of shuttle devicesoperable on a track system, the shuttles being engageable with theuprights of the framework of the grid-based storage system;

FIG. 8h is a schematic side view of the further form of the storage areaof the order picking system of FIG. 8g , showing the shuttle devices inposition within the uprights of the framework;

FIG. 9 is a schematic, perspective view of a further form of orderpicking system in accordance with the invention, the order pickingsystem comprising a further storage area comprising a grid-based storagearea adapted for use with larger storage bins or pallets;

FIG. 10 is a schematic, perspective view of a further form of theinvention, the order picking system comprising a storage area havingpresentation positions of differing sizes, the grid-based storage systemcomprising portions sized so as to accept storage bins or containers ofpredetermined but varying sizes;

FIG. 11 is a schematic, perspective view of a further form of theinvention, the grid-based storage area being associated with a zone picksystems on multiple levels in a CFC environment;

FIG. 12 is a schematic perspective view of a further form of theinvention showing a complete Customer Fulfilment Centre (CFC), the CFCcomprising a grid-based storage system having a zone pick order pickingsystem on one face, the remaining grid-based system comprising pickstations and peripherals adapted so as to function in said grid-basedsystem; and

FIG. 13 is a schematic view of a further form of order picking system inaccordance with one form of the invention, the system comprising twoforms of pick station in close proximity.

In the description below, ‘storage bins 10’ will be used to denotecontainers, bins or totes intended for the storage of inventory items,whilst ‘delivery containers DT’ will be used to denote containers, binsor totes intended to be filled to fulfil orders placed by customers, inan online retail environment or otherwise. It will be appreciated thatthis terminology is used for ease of reference and explanation withinthis document. However, it should be noted that the storage bins 10 andthe delivery containers DT may be of the same shape and configuration.Furthermore, delivery containers DT may be stored in bins 10 within thestorage system or any part thereof. It is the function of the bin,container or tote that defines the category of container rather than anychange in the actual size, shape, or configuration.

In one form of order picking system described below with reference toFIGS. 1 to 4, many pick aisles 100 may be arranged in a large warehouseenvironment often referred to as a Customer Fulfilment Centre (CFC) butfor ease of the present description, a single pick aisle 100 isdescribed below and illustrated in FIGS. 1 to 4. It will be appreciatedthat the number of pick aisles 100 is limited only by the size of thewarehouse building or CFC and that pick aisles 100 can be arranged overmany floors and in many different formats and arrangements. One exampleof pick aisle 100 described below is of a typical form but is describedfor example only and should not be considered limiting.

As shown in FIG. 1, one form of zone pick fulfilment system comprises apick aisle 100, the pick aisle 100 being bounded on one side by aproduct or item storage area 102 and being bounded on the other side byan order assembly area 104. Both the order assembly area 104 and thestorage area 102 extend substantially along the length of the pick aisle100, on both sides.

The order assembly area 104 comprises two parallel conveyors or portionsof conveyor 106, 108 running along the pick aisle 100, a first‘backline’ conveyor 106 and a second ‘station’ conveyor segments 108 aand 108 b. The backline conveyor 106 is linked to the station conveyorportions 108 a and 108 b by a series of diverts 110 and merges 112.

The pick aisle 100 further comprises a series of pick stations 114positioned at intervals along the length of the pick aisle 100, the pickstations 114 being located such that the station conveyor portions 108 aand 108 b run through the pick stations 114 a and 114 b.

The storage area 102 of the pick aisle 100 comprises a series of storagebin or container 10 presentation positions 116 which, when populatedwith bins or containers 10 or other forms of product, inventory or itemsin or on suitable storage receptacles, create a ‘pick face’ 118extending along the length of the pick aisle 100. The pick face 118comprises multiple layers of storage bins or bins 10 positioned so as topresent items to be picked (not shown) to operatives 120 present in thepick aisle 100.

In use, delivery containers DT are moved around the CFC to haveinventory items or products, previously ordered by a customer as part ofan order, placed therein. In the case of a given delivery container DT,this enters the pick aisle 100 described above as the control utility(not shown) has routed the said delivery container DT to that aisle 100as the storage area 102 of the particular pick aisle 100 comprises anitem required for the given customer order and the given deliverycontainer DT. It will be appreciated that delivery containers DT may berouted through every pick aisle in a CFC or infrastructure or conveyorconnections may exist within the CFC that enables delivery containers DTto only be routed through pick aisles 100 in which an item is to bepicked therein.

As the delivery container DT passes along the backline conveyor 106, itmay be diverted via the divert 110 to the station conveyor 108 a if thestorage area 102 in the region of the pick station 114 a comprises aproduct or item required in the given customer order associated with thegive delivery container DT. If the storage area 102 in the region of thepick station 114 a does not comprise a required item or product for thatgiven delivery container DT, the delivery container DT will bypass thepick station 114 a by continuing along the backline conveyor 106.

On arrival at the pick station 114 a, the delivery container DT comes toa controlled stop under the control of the computer control utility (notshown). Whilst held at the pick station 114 a, an operative 120 willpick the required inventory item or product from an identified storagecontainer or bin 10 located in the storage area 102 in to the deliverycontainer DT. The storage bin 10 will be identified by any suitablemethod. For example, a light may be activated at the appropriatepresentation position 116. Alternatively a display at the pick station114 may provide location information.

Once the required item is picked in to the delivery container DT, thedelivery container DT is moved on automatically under the control of thecomputer control utility (not shown) via the station conveyor portion108 a and the merge 112 on to the backline conveyor 106. The deliverycontainer DT will then continue on a journey around the CFC and berouted by the computer control utility (not shown) to the required pickstations 114 in any pick aisle 100 within the CFC.

It will be appreciated that the above is one form of zone pick systemand there are many variations and modifications to the above system thatare possible. For example, delivery containers DT may be manually pushedto and from the backline conveyor 106 or moved between pick stations 114manually.

In another example, no separate backline conveyor 106 is provided, soall delivery containers DT pass along station conveyors 108 only andtherefore pass through all pick stations 114. Furthermore, deliverycontainers DT may be automatically stopped at pick stations 114 or maycontinue moving there through, the operative picking items theretowhilst the delivery container DT is moving. Additionally, it will beappreciated that it is possible for delivery containers DT to bypasscomplete pick aisles 100 and only be routed through aisles 100 wherethere are items required to be picked into the relevant deliverycontainer DT.

In one further example, the conveyor systems 106, 108 are completelyreplaced by a manual system of trolleys pushed around the CFCenvironment by operatives who move along the pick face 118 to therequired storage locations 116, guided by computer devices displayingitem locations under the control of the computer control utility. Thecomputer devices may be handheld or may be trolley mounted.

The storage area 102, shown in more detail in FIGS. 3 and 4 comprises aframework 122 onto which storage bins 10 are placed by a crane device124. The framework comprises the presentation positions 116 in which thestorage bins or bins 10 are placed so as to form the pick face 118 alongthe length of the pick aisle 100. The framework 122 further comprisesstorage locations 126 (sometimes referred to as pre-pick positions)immediately behind the presentation positions 116 wherein storage bins10 are located. The storage locations 126 generally comprise storagebins 10 having the same inventory items therein as the storage bins 10in the presentation positions 116 in the pick face 118. However, thisneed not be the case.

The remaining storage positions 128 comprise storage bins 10 havingother inventory items therein. It will be appreciated that the inventoryitems are either of the same type as those in the storage bins 10 in thepresentation positions 116 and the storage locations 126, in the case offast moving goods, or other slower moving inventory items that may onlybe required to replace storage bins 10 in presentation positions 116less frequently.

In use, once the storage bin 10 in any given presentation position 116is emptied, for example when the operative 120 picks the final inventoryitem from the storage bin 10 in the presentation position 116, theoperative 120 removes the empty storage bin 10 to an alternative, remotelocation, and the storage bin 10 located in the pre-pick storageposition 126 immediately behind, is moved in to the presentationposition 116. The crane device 124 then fills the empty pre-pick storageposition 126 with a further storage bin 10 having the required inventoryitems therein.

It will be appreciated that the storage bins 10 in the pre-pickpositions 126 may be moved to the presentation positions 116 eithermanually, for example, by the operative 120 pulling he storage container10, or automatically by a conveyor, either driven or operating undergravity. It will be appreciated that there are many ways of moving thestorage bins 10 from the pre-pick positions 126 to the presentationpositions 116. It will also be appreciated that the storage bins or bins10 in the pre-pick storage positions 126 may contain the same type ofinventory item located in the storage bin 10 in the presentationposition 116. However, the computer control utility may determine thatfor future orders, a storage bin 10 comprising alternative inventoryitems may be more appropriately positioned in the presentation position116 and prepare for this in advance by locating the appropriate storagebin 10 in the storage position 126 in advance.

In this way, the items presented to the operative 120 may be dynamicallychanging over time and may be governed by a knowledge of future ordersor other outside influences such as seasonal changes.

It is a disadvantage of the zone pick system described above that, thestorage area can be a single point of failure. Should the crane device124 in any given pick aisle 100 fail, the use of the said pick aisle 100is affected. This can, for example, limit the use of the pick aisle 100to only the items remaining in the storage bins 10 already in the pickface 118. Prolonged inaction of the crane device 124 can cause problemsfor the whole CFC environment and in extreme cases can lead to customerorders being incomplete.

It is a further problem with the storage area of the pick aisle 100described above, that the velocity of turnover of items and productsstored in locations within the storage area 102 needs to be controlledin order to ensure that no one crane device 124 in one pick aisle 100 isoverloaded.

In the description that follows, features common to typical systemsdescribed above and the embodiments of the invention will be identifiedusing the same reference numerals.

One form of the invention will now be described with reference to FIGS.5, 6 and 7, stackable storage bins 10, are stacked on top of one anotherto form stacks 12. The stacks 12 are arranged in a frame structure 14 ina warehousing or manufacturing environment. FIG. 5 is a schematicperspective view of the frame structure 14. Each storage bin 10typically holds a plurality of product or inventory items 28, and theinventory items within a bin 10 may be identical, or may be of differentproduct types depending on the use to which the pick aisle 100 is put.Furthermore, the storage bins 10 may be physically subdivided toaccommodate a plurality of different inventory items 28.

The frame structure 14 comprises a plurality of upright members 16 thatsupport horizontal members 18, 20. A first set of parallel horizontalmembers 18 is arranged perpendicularly to a second set of parallelhorizontal members 20 to form a plurality of horizontal grid structuressupported by the upright members 16. The members 16, 18, 20 aretypically manufactured from metal. The storage bins 10 are stackedbetween the members 16, 18, 20 of the frame structure 14, so that theframe structure 14 guards against horizontal movement of the stacks 12of storage bins 10, and guides vertical movement of the storage bins 10.

The top level of the frame structure 14 includes rails 22 arranged in agrid pattern across the top of the stacks 12. Referring additionally toFIG. 6, the rails 22 support a plurality of robotic load handlingdevices 30. A first set 22 a of parallel rails 22 guide movement of theload handling devices 30 in a first direction (X) across the top of theframe structure 14, and a second set 22 b of parallel rails 22, arrangedperpendicular to the first set 22 a, guide movement of the load handlingdevices 30 in a second direction (Y), perpendicular to the firstdirection. In this way, the rails 22 allow movement of the load handlingdevices 30 in two dimensions in the X-Y plane, so that a load handlingdevice 30 can be moved into position above any of the stacks 12.

Each load handling device 30 comprises a vehicle 32 which is arranged totravel in the X and Y directions on the rails 22 of the frame structure14, above the stacks 12. A first set of wheels 34, consisting of a pairof wheels 34 on the front of the vehicle 32 and a pair of wheels 34 onthe back of the vehicle 32, are arranged to engage with two adjacentrails of the first set 22 a of rails 22. Similarly, a second set ofwheels 36, consisting of a pair of wheels 36 on each side of the vehicle32, is arranged to engage with two adjacent rails of the second set 22 bof rails 22. Each set of wheels 34, 36 can be lifted and lowered, sothat either the first set of wheels 34 or the second set of wheels 36 isengaged with the respective set of rails 22 a, 22 b at any one time.

When the first set of wheels 34 is engaged with the first set of rails22 a and the second set of wheels 36 are lifted clear from the rails 22,the wheels 34 can be driven, by way of a drive mechanism (not shown)housed in the vehicle 32, to move the load handling device 30 in the Xdirection. To move the load handling device 30 in the Y direction, thefirst set of wheels 34 is lifted clear of the rails 22, and the secondset of wheels 36 is lowered into engagement with the second set of rails22 a. The drive mechanism can then be used to drive the second set ofwheels 36 to achieve movement in the Y direction.

In this way, one or more robotic load handling devices 30 can movearound the top surface of the stacks 12 on the frame structure 14, asshown in FIG. 4 under the control of a centralised control utility (notshown). Each robotic load handling device 30 is provided with liftingmeans 38 for lifting one or more bins 10 from the stack 12 to access therequired products.

The body of the vehicle 32 comprises a cavity 40, the cavity 40 beingsized so as to hold a storage bin 10. The lifting means 38 preferablycomprises winch means and a storage bin 10 gripper assembly 39. Thelifting means 38 lifts a storage bin 10 from the stack 12 to within thecavity 40 in the body of the vehicle 32.

In this way, using a plurality of robotic load handling devices 30 on agrid-based storage system allows multiple products to be accessed frommultiple locations in the grid and stacks 12 at any one time.

A first embodiment of an order picking system in accordance with oneform of the invention is shown in FIGS. 7a, 7b and 7c . As can be seenin FIG. 7a , the first embodiment comprises a pick aisle 100 in whichthe storage area 102 comprises presentation positions 116 in whichstorage bins 10 are located to create a pick face 118.

In the context of one example of order picking system in accordance withone form of the invention, and with reference to FIGS. 7a, 7b and 7c , arobotic load handling device 30 removes a storage bin 10 containinginventory items 28 required for picking in to customer orders thereinfrom a stack 12. The load handling device 30 transports the saidrequired storage bin 10 to an output port 130 as shown in more detail inFIG. 7b . At the output port 130, the storage bin 10 is lowered by theload handling device 30 to a landing portion 132 in a pre-pick position126.

As shown in FIG. 7b , the pre-pick position 126 in to which the storagebin 10 is lowered will depend on the presentation position 116 for whichthe storage bin 10 is ultimately destined. Typically, there are threepresentation positions 116 in substantially positioned in column-likeplacements along the pick face 118 although it will be appreciated thatthis is dependent on the size of the storage bins 10, larger storagebins 10 may result in fewer presentation positions 116 on the pick face118 and smaller storage bins 10 may result in a larger number ofpresentation positions 116 on the pick face 118. Furthermore, thearrangement of the presentation positions 116 may depend on the drop offlocations and the arrangement of landing portions 132. Any suitablearrangement of presentation positions 116 suitable to achieve therequired throughput of storage bins 10, in the particular context of thepicking system, at the pick aisle 100 may be envisaged.

As shown in more detail in FIG. 7b , in order for the pre-pick positions126 for the presentation positions 116 not to impinge on storage bins 10being lowered by alternative load handling devices 30 to other pre-pickpositions 126, a staggered set of pre-pick positions 126 may berequired. Advantageously, this can ensure that ‘faster moving’ inventoryitems 28—namely those more frequently ordered by customers or those ofwhich customers typically order a plurality—are continually andregularly placed in the pre-pick position 126 in order for a swiftreplacement to be possible when the storage bin 10 in the presentationposition 116 is empty. Although as previously described, the same itemsor products need not be in each of the storage containers 10 in thepre-pick positions 126.

As shown in more detail in the simplified side view of FIG. 8a , eachpre-pick position 126 comprises a landing portion 132 on to which theload handling device 30 lowers the storage bin 10. The landing portion132 comprises a device acting as means for moving the storage bin 10from the dropped position, in a substantially lateral direction, in acontrolled manner, toward the presentation position 116 as and whenrequired by the operative 120 in the pick aisle 100. It will beappreciated that there are many ways in which the skilled person mayachieve this objective and the following examples are not to beconsidered limiting, any suitable form of mechanism may be used tofulfil this function.

One form of moving device may comprise a driven roller conveyor section133 located at the landing portion 132 as shown in FIG. 7b . The drivenconveyor 133 may comprise a series of rollers powered such that onactivation of the driver, any storage bin 10 in position on the landingportion 132 will move under the control of the driven conveyor section133 into the next pre-pick storage position 126 or in to thepresentation position 116.

It will be appreciated that the conveyor section 133 may be driven by amotor or any other suitable form of driver, but may also be manuallyactivated by a lever, crank or other mechanical device, under thecontrol of the operative 120.

The conveyor section 133 may further comprise a bin stop (not shown).The bin stop acts so as to prevent the movement of the storage bin 10from the landing portion 132 in to pre-pick positions 126 or in to thepresentation position 116. The bin stop may be under the control of thecomputer control utility, thereby enabling the system to control themovement of the storage bins 10 in to presentation positions 116 onlyonce previously depleted storage bins 10 in the presentation positions116 have been moved by the operative.

Each output port 130 comprises a grid space defined by the tracks orrails 22 in the grid-based storage area 102. Beneath the output port 130is a column of the storage area 102 not populated with stacks 12 ofstorage bins 10 that acts as a column 131 down which the load handlingdevice 30 lowers the or each storage bin 10 required to be delivered tothe pick face 118. The output column 131 further comprises sensor means(not shown) to detect the presence or absence of the lifting device 38and or the storage bin gripper assembly 39 in the output column 131. Theoutput column further comprises sensor means (not shown) in the vicinityof the landing portion 132 to detect the presence or absence of astorage bin 10 on the landing portion 132.

In use, the system of FIGS. 7a, 7b and 7c operates as follows. A roboticload handling device 30 is controllably moved in to position above astack 12 of storage bins 10 in which the top storage bin 10 containsitems required to be picked in to a customer order in an online retailenvironment. The robotic load handling device 30 lowers the liftingdevice 38 and the storage bin 10 gripper assembly 39 engages with thestorage bin 10 in the top position in the stack 12. The liftingmechanism 38 is reeled in and the storage bin 10 is moved upwardly offthe stack 12 and lifted in to the cavity in the body 32 of the roboticload handling device 30. Once the storage bin 10 is fully within thebody 32, the robotic load handling device 30 is moved under the controlof the computer control utility to the output port 130.

Once positioned at the output port 130, above the output column 131, therobotic load handling device 30 lowers the storage bin 10, substantiallyreversing the storage bin 10 lifting process, the lifting device 38lowering the storage bin 10 until located on the landing portion 132.Sensors (not shown) in the output column 131 in the vicinity of thelanding portion 132 detect the presence of the storage bin 10 on thelanding portion 132 and the bin gripper 39 disengages from the storagebin 10. Once disengaged, the bin gripper 39 is reeled back in to thebody 32 of the load handling device 30. The movement of the bin gripper39 is monitored by further sensors (not shown) in the output column 131to ensure the load handling device 30 is fully disengaged from thestorage bin 10. If the storage bin 10 is detected on the landing portion132 and the bin gripper 39 is detected as disengaged from the storagebin 10, the computer control utility can act on so as to drive thedriven conveyor section 133 to move the storage bin 10 in to apresentation position 116 or a further pre-pick storage position 126dependent on the output column 131 in to which the storage bin 10 hasbeen deposited.

It will be appreciated that the driven roller conveyor section orsections 133 are under the control of the computer control utility (notshown), the conveyor section or sections 133 only being powered when thestorage bin 10 is in position on the landing portion 132. The bin stopacting to prevent movement of the storage bin 10 before the subsequentstorage bin 10 position 116, 126 is free to accept the storage bin 10.

Once the required storage bin 10 is in the required presentationposition 116 of the pick face 118, the operative 120 may pick itemstherefrom in to delivery containers DT present on the station conveyor108 a at the pick station 114 a in the pick aisle 100. The deliverycontainer DT comprising the picked item may then be moved along thestation conveyor 108 a and merge on to the backline conveyor 106 via themerge 112. The said delivery container DT may then be moved to otherpick aisles 100 via conveyor connections (not shown) and onward to otherpick stations 114 within the CFC.

Once the required items fulfilling the customer order, or a part of thecustomer order, have been picked therein, the delivery container DT isrouted under the control of the computer control utility to a dispatcharea (not shown) for loading and dispatch to a customer.

It will be appreciated that the presentation positions 116 comprisestorage bins 10 at all times unless being replenished by a storage bin10 from the “pre-pick” positions 126. However, in order for storage bins10 comprising inventory items or products to replace storage bins 10having been emptied by operatives 120, the empty storage bin 10 must bemanually removed by the operative 120. The empty storage bins 10 may bemanually collected by further operatives 120 and moved to an input port(not shown) of the storage area where further inventory items orproducts can be manually or robotically placed therein.

Alternatively the storage bins 10 removed from the presentationlocations 116 once the inventory items or products therein are depletedmay be placed on the station conveyor 108 and or the backline conveyor106 for removal to a remote location wherein the storage bins 10 areretuned in to the storage area 102 for re-filling or other use. In afurther form of the invention, a further conveyor may be located, forexample above the station 108 and or backline conveyor 106 or above thepick face 118, to remove empty storage bins 10 to said remote collectionpoint (not shown).

However, it is an advantage of such grid-based order picking and storagesystems that the storage bins 10 remain captive in the system. Manualmovement of the storage bins 10 may need to be avoided as damage may becaused or cleaning may be required.

Accordingly, in another aspect of the first embodiment of the inventionthe pick face 118 is provided with input locations in to the storagearea 102. The input locations comprise empty presentation locations 116in the pick face 118 where an operative 120 may place an empty storagebin 10 on a moving device acting so as to move the empty storage bin 10from the presentation position 116 to an empty pre-pick position 126 andagain to a landing portion 132. Once the empty storage bin 10 is inposition on the landing portion 132 a robotic load handling device 30can be moved under the control of the computer control utility, to pickup the empty storage bin 10 and reel said bin 10 in to the body of theload handling device 30. The load handling device 30 may then be movedto a position where the empty storage bin 10 is required or can berefilled with inventory items or products.

It will be appreciated that this is the reverse process of routing thestorage bin 10 comprising inventory items or products to thepresentation position 116. However, given the number of inventory itemsor products in each storage bin 10 in the presentation positions 116 inthe pick face 118, there will be a slower turnover of empty storagecontainers 10. Accordingly, fewer reverse input presentation positionswill be required along the length of the pick aisle 100. There may be asfew as 1 input presentation position for every 30 output presentationpositions 116. p In a further form of the first embodiment of theinvention, the delivery containers DT located at the pick stations 114may be input in to the storage area once items required have been pickedtherein. In the same manner that empty storage bins 10 may be returnedin to the storage area via reverse presentation positions 116, deliverycontainers DT may be placed in storage bins 10 and input to the storagearea for later assembly of a full customer order. In this way, customerorders may be part picked and stored in the storage area within deliverycontainers DT within storage bins 10 in stacks 12.

It will be apparent to a skilled person in the art that the movingconveyor sections 133 need not comprise driven roller conveyor section133 but may comprise driven belt conveyors. It will be appreciated thatany other suitable form of driven conveyors may be used capable ofmoving storage bins 10 under control of a computer control utility in anorder picking and storage system.

In a further form of the first embodiment of the invention, as shown inFIG. 7c , the pick aisle 100 comprises operatives 120 moving trolleys134 along the pick aisle 100 instead of a conveyor 106, 108 and pickstation 114 arrangement. The trolleys 134 comprise a plurality ofdelivery containers DT capable of being moved by the operative along thepick aisle 100 in front of the pick face 118. In this form of theembodiment of the invention, the operative 120 is provided with acomputer controlled display and scanning device, the device comprisingitem location information relating to a given customer order andpredetermined delivery container DT position information.

It will be appreciated that the computer and/or scanner may of anysuitable form or configuration suitable for the purpose and many formsare such device would be known to a person skilled in the art forimplementation in such a system as described herein. The computer devicemay be trolley mounted and may use voice synthesis and voice recognitiontechnology but need not be so configured, any suitable configuration forthe purpose may be envisaged.

In use, the operative or operatives 120 position the trolley 134adjacent a presentation position 116 from which an item is required asinstructed by the computer controlled device. The or each operative 120picks the item from the storage container 10 in the appropriatepresentation position 116, scans the item, and places the item in to thedelivery container DT on the trolley 134. The operative may also berequired to scan the delivery container DT on placing the scanned itemin to the predetermined delivery container DT so as to ensure thecorrect item is in the correct delivery container DT.

The operative 120 then moves along the pick aisle 100 repeating theprocess until all items required from the given pick aisle 100 arepicked in to the appropriate delivery containers DT on the trolley 134.The operative 120 may then continue to other pick aisles 100 within theCFC and moved there through as required. Once all the required itemshave been picked to fulfil the portions of the customer order comprisingthe delivery containers DT on the trolley 134, the trolley 134 is movedto dispatch for unloading and onward transit to customers.

Alternatively, the completed delivery containers DT may be placed in tostorage bins 10 and placed in to the grid-based storage area 102 forfuture picking, combination with other related delivery containers DTfor a given order, or dispatch. The nested storage bins 10 and deliverycontainers DT may be routed via any of the conveyor means describedabove to a remote location for manual, automated or robotic replacementin the system.

It will be appreciated that in any given CFC operation, a combination ofconveyor pick aisles 100 and trolley 134 pick aisles and operatives 120may be used to fulfil all or part of customer orders.

It will be appreciated that, in the first embodiment of the invention,the use of the grid-based storage area 102 enables all presentationpositions 116 in all pick aisles 100 to be serviced at all times.Failure of a load handling device 30 will not stop the system operating,unlike typical storage areas 102 currently serviced by crane devices124.

A second embodiment of the invention will be described with reference toFIGS. 8a, 8b and 8c . Items referenced in the systems described aboveboth in the preamble and the first embodiment of the invention willretain the same reference numerals.

FIG. 8a shows a perspective schematic view of an alternative form ofstorage area 102 located in a pick aisle 100 of a CFC. The conveyors106, 108, the pick stations 114 and the order assembly area are asdescribed with reference to FIGS. 7a and 7b or alternatively the trolleypick solution of FIG. 7c may be envisaged.

The storage area 102 of the second embodiment remains of the grid-basedtype, comprising stacks 12 of storage bins 10 located within a framework14, the framework 14 comprising uprights 16 supporting a grid structurelocated above the stacks 12. Load handling devices 30 operate on tracks22 mounted on the grid structure of the framework 14. The grid structuredefining grid spaces within which the footprint of a stack 12 of storagebins 10 will fit.

In common with the first embodiment, the framework 14 further defines anumber of output ports 130 and output columns 131 down which storagebins 10 may be lowered by the lifting device 38 and bin gripper device39 of the load handling device 30.

In the second embodiment of the invention, the output column 131 againcomprises a series of landing portions 132. However, in the secondembodiment of the invention the landing portions 132 comprise rollerconveyor sections 233. The roller conveyor sections 233 of the secondembodiment are not powered or driven. The roller conveyors 233 comprisea series of rollers 234 mounted on a substructure 236. The rollers arefree to rotate when located in the substructure 234.

As can be seen in FIGS. 8a and 8b , each output port 130 and outputcolumn 131 associated with a given presentation position 116 comprises adifferent number of roller substructures 236, again the staggered numberof landing positions 132 is defined by the number of presentationpositions 116 required in the pick face 118. The specific numbers oflanding portions 132 and output ports 130 and columns 131 may bedifferent than shown and described in the present example.

The substructure 236 of the landing portion 132 is located within theoutput column 131 in a similar manner to that described previously withreference to the first embodiment of the invention. Each landing portion132 comprising the substructure 236 when in situ within the outputcolumn 131 is located in a substantially horizontal position withreference to the uprights of the framework 14 of the storage area 102when there is no storage bin 10 located thereon. As shown in FIG. 8b theuppermost landing portion 132 absent a storage bin 10 comprises asubstructure 236 positioned in a substantially horizontal manner withinthe output column 131 and relative to the uprights of said column 131.

It will be noted that the remaining landing portions 132 in FIG. 8bcomprise storage bins 10 located on the rollers of the substructure 236.However, substructures 236 occupied, with storage bins thereon, are atan angle relative to the horizontal. Whilst not to scale in thedrawings, the angle may be 5 degrees from the horizontal but it will beappreciated that any angle suitable for the required purpose may beused.

The substructure 236 further comprises two guide uprights 238 mounted onsaid substructure 236 substantially perpendicular to the base of thesubstructure 236. The guide uprights 238 extend from two corners of theshort side of the substructure 236 upwardly, substantially parallel tothe framework uprights 14 of the framework 14 in the output columns 131of the storage area 102. The guide uprights 238 are positioned on thesubstructure 236 of the landing portion 132 so as to guide a storage bin10 lowered thereon. The guide uprights 238 extend upwardly from thesubstructure and are sized so as to be taller than the height of astorage bin 10 in use in the system.

The substructures 236 of the landing portions 132 are pivotally mountedwithin the output column 131. In this way the landing portions are freeto tip downwardly toward the presentation positions 116 by apredetermined angle.

Each landing portion 132 is provided with a storage bin 10 stop device240. The bin stop device 240 is roatably mounted on each of the landingportions 132 and the presentation portions 116, beneath the rollersmounted in the substructure 236. The bin stop device may comprise asubstantially vertically extending member 242 capable of protrudingbetween the rollers mounted in the substructure 236. The bin stop device240 may further comprise a longitudinally extending portion (not shown)beneath the rollers connected to the vertically extending member 242,the longitudinally extending portion being pivotally mounted on thesubstructure 236. In the present embodiment, the bin stop 240 issubstantially L-shaped. One of the rollers (not identified) in theroller bed mounted in the substructure 236 is spring loaded within thesubstructure 236 and when forced down by the presence of a storage bin10 on the bed of rollers acts so as impinge on the longitudinallyextending portion of the bin stop device 240 underneath the rollers. Thebin stop device 240 may move from a first position where the verticallyextending member 242 protrudes through the rollers to a second positionwhere the vertically extending member 242 is beneath the uppermostsurface of the rollers. There may be a mechanical advantage such that asmall movement in the roller is magnified to a larger movement of thevertically extending portion 242. Movement of the spring mounted rollerunder the force of a storage bin 10 on the rollers, pivots thelongitudinally extending member such that the vertically extendingportion 242 protrudes through the rollers.

In use, with reference to FIGS. 8a, 8b and 8c , a storage bin 10 istransported to the output port 130 as described above with reference tothe first embodiment of the invention. The storage bin 10 is lowered bythe lifting means 38 of the load handling device 30 down the outputcolumn 131. As the storage bin 10 approaches the landing position 132the storage bin 10 begins to engage the guide uprights 238 of thesubstructure 236. The lifting means 238 continues to lower the storagebin 10 until the storage bin 10 is in position on the rollers rotatablymounted on the substructure 236. Once in this position, the gripperassembly 39 of the lifting device 38 is disengaged from the storage bin10 and is reeled back in to the load handling device 30.

As the gripper device 39 disengages and is moved upwardly, it passes theuppermost part of the guide uprights 238. Once the gripper device 39passes this uppermost part of the guide uprights 238, the substructure236 is free to pivot from the substantially horizontal position bydownwardly toward the presentation positions 116.

As the rollers mounted within the substructure 236 are free to rotate,the storage bin 10 will move toward the presentation position 116 underthe weight of the storage bin 10, under gravity.

In the case of the uppermost landing position 232 and presentationposition 116 in FIG. 8b , once the storage bin 10 is in situ on thesubstructure 236 of the landing portion 132 and the gripper device 39 ofthe load handling device 30 has been retracted, the substructure 236will tip downwardly at the end adjacent the presentation position 116,and the storage bin 10 will move under gravity in to the presentationposition 116.

As there is no storage bin in the uppermost presentation position 116 ofthe pick face 118 in this example, the bin stop device 240 does notoperate and the storage bin is free to roll forward on the rollers fromthe landing position 132 in the pre-pick position 126, to thepresentation position 116 a.

With reference to the second layer of storage bins 10 in the pre-pickpositions 126 of FIG. 8b , the presence of a storage bin 10 in thepresentation position 116 acts so as to activate the bin stop device240.

Movement of the spring loaded roller under the force of a storage bin 10on the rollers of the presentation portion 116, pivots thelongitudinally extending member beneath the rollers, such that thevertically extending member 242 of the bin stop device 240 protrudesthrough the rollers at a position on the roller bed adjacent the firstpre-pick position 126 b, thereby preventing the storage bin 10 b′ fromrolling under gravity in to the storage bin 10 in the presentationposition 116 b. In a similar fashion, the presence of a storage bin 10b′ in the pre-pick position 126 b activates the bin stop 240 in thesubstructure 236 of the roller conveyor section in the pre-pick position126 b. The activated bin stop 240 prevents the storage bin 10 b″ fromrolling under gravity from the landing portion 132 b in to the storagebin 10 b′ in the pre-pick position 126 b.

From the above and with reference to FIGS. 8b and 8c , it will beappreciated that the presence of a storage bin 10 on any roller conveyorsection 133 activates the bin stop device 240 and prevents the nextstorage bin 10 in the system from moving under gravity in to the nextposition in the system.

It will be appreciated that the use of a bin stop device 240 in this wayis required as manual removal of the storage bin 10 in the presentationposition 116 in the absence of the pre-pick storage bins 10 beingstopped by the bin stop device 240 may require excess force.Furthermore, on removal of the storage bin 10 in the presentationposition 116 any storage bins 10 not stopped may move quickly undergravity and could cause damage or injury to the operative 120 or to theitems and products in the storage bin 10.

It will be appreciated that the bin stop device 240 described above withreference to FIGS. 8b and 8c is only one form of bin stop mechanism thatmay be used and any other mechanical, electromechanical, magnetic or anyother suitable form of bin stop device capable of stopping the movementof bins on gravity fed roller conveyor sections may be used.

It is an advantage of the second embodiment of the invention that thesystem for moving storage bins 10 from the point at which they aredeposited by the load handling devices 30 to the presentation positions116 requires no power and is a relatively simple and effectivemechanical system. This removes complexity from the system and removesthe need for the computer control utility to be controlling the precisemovement of the storage bins 10 towards the pick face 118.

It will be appreciated that in common with the first embodimentdescribed above, empty storage bins 10 may be input to the system atspecially configured presentation positions 116 that act in the samemanner to that described above with reference to storage bins 10 beingfed in to the presentation positions 116. Whilst a mechanical systemcould be envisaged. It would be also possible for the input positions tobe powered in the manner descried with reference to the firstembodiment. Again, fewer input positions would be required compared withthe number of output presentation positions 116.

Again, it will be appreciated that the conveyor-based order assemblyarea 104 may be replaced with the trolley 134 pick solution describedwith reference to FIG. 7c of the first embodiment, the use of thetrolley pick aisles remaining as described above.

A third embodiment of the invention will be described with reference toFIG. 8d . Items referenced in the systems described above both in thepreamble and the first and second embodiments of the invention willretain the same reference numerals.

The third embodiment of the invention comprises an alternative form ofoutput column 331 and method of operation thereof.

The output column 331 of the third embodiment comprises a bin liftdevice 300. The bin lift device 300 is operable within the output column331 and services all the presentation positions 116 of the pick aisle100.

The bin lift device 300 comprises a landing portion 332 comprising asection of powered conveyor 304. The bin lift device 300 moves up anddown the output column 331 under the control of the computer controlutility (not shown). The bin lift device 300 may comprise any suitableform of lift device capable of receiving storage bins 10 delivered byload handling devices 30 and transporting said storage bins 10 topresentation positions 116 of the pick face 118 of the storage area 102of the pick aisle 100.

In use, the load handling device 30 lowers a storage bin 10 through theoutput port 30 in to the output column 331. The bin lift device 300 maybe moved upwardly within the column to meet the storage bin 10 beinglowered by the load handling device 30.

The storage bin 10 is deposited on the landing portion 332 of the liftdevice 300 and the bin gripper 39 of the lifting means 38 is disengagedfrom the storage bin 10 and retracted in to the body 32 of the loadhandling device 30.

Once the storage bin 10 is in situ on the landing portion 332 of the binlift device 300, the bin lift device 300 is moved to be adjacent thepresentation position 116 of the pick face 118 of the pick aisle 100 inthe CFC. The driven roller conveyor of the landing portion 332 of thebin lift device 300 is activated so as to drive the storage bin 10 fromthe bin lift device 300 in to the presentation position 116. Once thestorage bin 10 is in situ in the presentation position 116, the bin liftdevice 300 may move to the top of the output column 331 in order toreceive another storage bin 10.

In this way, a single bin lift device 300 is operable in each outputcolumn 331 of the pick face 118 again avoiding a single point offailure, but wasting less storage space with pre-pick positions 126.

It will be appreciated that this the case of the third embodiment, asingle output column 331 could service the presentation positions 116 oftwo pick aisles, one on either side of the column 331. Furthermore, itwould be possible for a single output column to service multiple levelsof pick aisles 100. For example, in one form of the third embodiment ofthe invention, two pick aisles 100 are located on a ground floor and twopick aisles 100 are located on a mezzanine level immediately above. Itwill be appreciated that the grid-based storage system may be positionedon the ground floor whilst extending upwardly over many floors. In thiscase, a single output column 331 could service the presentationpositions 116 on both the ground floor and the mezzanine level, thesystem having a pick face 118 on each floor.

It will be appreciated that a bin lift device 300 will be required inany output column 331 having presentation positions 116 therein.

In another form of the invention with reference to FIGS. 8e and 8f , thebin lift device 300 present in each output column 331 as describedabove, is replaced with a series of shuttle devices 310. Each shuttledevice 310 is moveable around a frame 340, the frame 340 beinginterposed between the uprights of the output columns 331 as shown inFIG. 8 f.

The frame 340 comprises two tracks, each track comprising a firstportion 342 substantially horizontal and extending longitudinally alongthe base of the output columns 331, and a second portion 344substantially horizontal and longitudinally extending along theunderside of the rails or tracks on which the load handling devices 30are operative.

The first and second track portions 342 and 344 are linked by aplurality of substantially vertically extending track sections 346, thenumber of substantially vertically extending track sections 346 matchingthe number of uprights in the output columns 331. In this way, the pitchof the substantially vertical track sections 346 substantially matchesthe pitch of the uprights of the output columns 331.

The frame 340 is disposed between the uprights of the output columns 331so as to create a framework on which a shuttle devices 310 can run.

Each shuttle device 310 comprises a vehicle base 312 the base 312carrying a section of conveyor 333. Each shuttle device 310 furthercomprises wheels or any other suitable form of moving mechanism, thewheels or moving mechanism being adapted so as to be moveable along yetcaptive within or on the tracks 342, 344, 346 of the frame 340.

The track portions 342, 344 and the track sections 346 of the frame 340may comprise longitudinally extending, grooved, extruded members, thewheels or moving means comprising a geared or wheel mechanism captive inthe grooved extruded members.

However, it will be appreciated that there are many ways known to aperson skilled in the art of achieving this objective. For example, thetracks or may not be grooved but may be of a c-shaped cross section, thecaptive wheel mechanism being held in place by the distal ends of thec-shape.

The joints (not shown) between the substantially vertical extendingtrack sections 346 and the substantially horizontal longitudinallyextending track portions 342, 344 are adapted so as to allow the wheelsor moving means of the shuttle devices 340 to move from a substantiallyvertically extending section of track 346 to a substantiallyhorizontally extending portion of track 342, 344.

In this way a shuttle device can pass along the base of the outputcolumns 331 of the storage area 102 on the track portion 342, travelupwardly on the track sections 346 within the output columns 331 andalong the uppermost track portion 344.

It will be appreciated that the nature of the frame 340 allows for aplurality of shuttle devices to be operable on the frame at any time asit is possible for a shuttle device 340 to pass along the substantiallyhorizontal, longitudinally extending tracks 342 beneath shuttle devices340 located and operable on the substantially vertical sections of track346.

In use, a load handling device 30 positioned at the top of the outputcolumn 331 lowers a storage bin 10 required for a presentation position116 associated with the given output column 331, on to the shuttledevice 310. Once the storage bin 10 is in situ on the shuttle device310, the gripper mechanism 39 and lifting device 38 of the load handlingdevice 30 disengage from the storage bin 10 and retract or reel back into the load handling device 30.

Once the storage bin 10 is disengaged from the gripper device 39, andthe gripper device 39 and lifting means 38 are clear of the outputcolumn 331, the shuttle device 310 moves in a substantially verticaldirection on the section of track 346 within the output column 331 andis paused under the control of the computer control utility at a levelcorresponding with the presentation position 116 at which the storagebin 10 is required to replace a previously removed storage bin 10.

Once in position, the conveyor 333 on the shuttle device 310 isactivated such that the storage bin 10 moves from the device in to theempty presentation position 116.

Once the storage bin 10 is in position in the presentation position 116,the shuttle device 310 may be repositioned to receive the next storagebin 10. It will be appreciated that the next presentation position 116that may require refilling may be associated with the same output column331 or may be associated with an alternative output column 331positioned at a different position in the pick face 118.

In the event that the presentation position 116 is in the same outputcolumn, the shuttle device 310 and climbing means 316 act in the mannerdescribed above to receive the required storage bin 10 and move it tothe required position 116.

In the event that the presentation position 116, to be filled by thedelivered storage bin 10, is in a different output column 331, theshuttle device 310 is moved on the track sections 346 in either anupward direction or a downward direction dependent on the position ofother shuttle devices and the location of the presentation position 116to be filled. On reaching either of the substantially horizontallyextending track portions 342, 344, the wheel or moving mechanism of theshuttle device 310 engages the relevant portion of the track 342, 344and is moved under the control of the computer control utility to thebase of the output column 331 associated with the presentation position116 requiring the storage bin 10 to be delivered thereto. Once inposition at the base of the required output column 331, the shuttledevice 310 engages the track sections 346 and the shuttle device 310 ismoved in to the output column 331. The procedure for receiving a storagebin 10 and transferring said bin 10 in to the presentation position 116as described above is repeated.

It will be appreciated that the shuttle devices 310 are controlled bythe computer control utility in common with all of the previouslydescribed embodiments and forms of the invention.

In yet another form of the invention, in the context of the presentembodiment, as shown in FIGS. 8g and 8h , the bin lift device 300 ofFIG. 8d is again replaced by a shuttle device 310. The shuttle device310 comprises a vehicle base 312 the base 312 carrying a section ofdriven conveyor 333. The shuttle device 310 is mounted on asubstantially horizontal, longitudinally extending rail or track 313running substantially parallel to the pick face 118 at the base of thestorage area 302, the longitudinally extending rail or track 313 passingbeneath the base of the uprights 16 bounding the output column 331 ofthe grid-based storage area 102.

The shuttle device 310 further comprises wheels 314, or any othersuitable form of moving means, adapted so as to allow movement of theshuttle device 310 in both directions along the longitudinally extendingrail or track.

The shuttle device 310 further comprises climbing means 316 adapted soas to allow the shuttle device 310 to ascend the output column 331. Theclimbing means 316 may take any suitable form enabling movement of theshuttle device 310 in the substantially vertical direction up and downthe output column 331 and enabling the shuttle device to pause atpositions within the output columns 331 corresponding to thepresentation positions 116.

It will be appreciated that the climbing means 316 may be integral withthe shuttle device 310 or may take the form of a separately functioninglift device on to which the shuttle device 310 is manoeuvred, theseparate lift device running up and down the output column 331 andpausing at the presentation positions 116.

In use, the shuttle device 310 is moved under the control of thecomputer control utility along the longitudinally extending rails ortracks to the base of an output column 331. Once in position at the baseof a desired output column 331, the climbing means engages the uprightsof the output column 331 and is moved under the control of the computercontrol utility in an upward direction.

As previously described above with reference to the system of FIGS. 8eand 8f , a load handling device 30 positioned at the top of the outputcolumn 331 lowers a storage bin 10 required for a presentation position116 associated with the given output column 331 on to the shuttle device310. The gripper mechanism 39 and lifting device 38 of the load handlingdevice 30 is then disengaged and retracted or reeled back in to the loadhandling device 30. Once the storage bin 30 is disengaged from thegripper device 39, the shuttle device 310 moves in a vertical direction,downwardly and is paused under the control of the computer controlutility at a level corresponding with the presentation position 116 atwhich the storage bin 10 is required to replace a previously removedstorage bin 10.

Once in position, the conveyor on the shuttle device 310 is activatedsuch that the storage bin 10 moves from the device in to the emptypresentation position 116. Once the storage bin 10 is in position in thepresentation position 116, the shuttle device 310 may be positioned toreceive the next storage bin 10.

It will be appreciated that the next presentation position 116 requiringrefilling may be associated with the same output column 331 or may beassociated with an alternative output column 331 positioned at adifferent position in the pick face 118.

In the event that the presentation position 116 to be filled by thedelivered storage bin 10 is in the same output column, the shuttledevice 310 and climbing means 316 act in the manner described above toreceive the required storage bin 10 and move it to the required position116.

In the event that the presentation position 116 to be filled by thedelivered storage bin 10 is in a different output column 331, theshuttle device 310 is moved via the climbing means 316 in a downwarddirection to the base of the output column 331. Once at the base of theoutput column 331, the shuttle device 310 engages the longitudinallyextending rail or track 313 and is moved under the control of thecomputer control utility to the base of the output column 331 associatedwith the presentation position 116 requiring the storage bin 10 to bedelivered thereto. Once in position at the base of the required outputcolumn 331, the shuttle device 310 engages the uprights of the outputcolumn 331 and the procedure above is repeated.

It will be appreciated that in the embodiments described with referenceto any of FIGS. 8d, 8e, 8f, 8g, and 8h , the conveyor 333 on the shuttledevices 310 may be driven roller conveyor or driven belt conveyor andmay be powered by any suitable means.

Using the shuttle device 310 in the manner described in any of theembodiments described with reference to FIGS. 8d, 8e, 8f, 8g and 8henables a plurality of columns to be serviced by a single shuttle device310.

It will be appreciated that, as shown in FIGS. 8e, 8f, 8g and 8h aplurality of shuttle devices 310 may be able to operate on thelongitudinally extending rails or tracks as one shuttle device 310 canpass beneath a shuttle device 310 in position in an output column 331.

It will further be appreciated that longitudinally extending rails ortracks 318 may also run the length of the pick face 118, at the top ofthe output columns 331, substantially parallel to the rail or track 313at the base of the storage area 302. It will be noted that only a singlerail or track 313 is required at the base of the output columns 331,however at the top of the output columns a pair of rails or tracks 318will be required in order that the shuttle devices 310 and the rails ortracks 318 on which they run do not impinge on the action of the loadhandling devices 30 and the movement of the storage bins 10.

In this way it is possible for the shuttle devices 310 to pass up anddown the output columns 331 and also pass up one output column 331,across the top of the said output column 331, beneath the level of thesurface on which the load handling devices 30 are operable, and alongthe underside of said surface to a further output column 331 and downsaid output column 331. It will be appreciated that in order to achievethis the shuttle device 310 comprises at least one retaining mechanismadapted so as to engage with the bottom longitudinally extending rail ortrack 313, the uprights of the output columns 331 and the rails ortracks 318 running longitudinally along an upper portion of the outputcolumns 331.

As described above with reference to FIGS. 8e and 8f said rails ortracks 313, 318 may comprise longitudinally extending, grooved, extrudedmembers, the retaining mechanism comprising a geared or wheel mechanismcaptive in the grooved extended members until the handover point betweenthe substantially vertically extending uprights of the output columnsand the substantially horizontal rails or tracks 313, 318. However, itwill be appreciated that there are many ways known to a person skilledin the art of achieving this objective. For example, the tracks or rails313, 318 may not be grooved but may be of a c-shaped cross section, thecaptive wheel mechanism being held in place by the distal ends of thec-shape.

In this way fewer shuttle devices 310 are required than the number ofoutput columns 331 in the pick face 118. For example, it may be possiblefor one shuttle device to cover 10 or more output columns 331. However,the number of shuttle devices 310 required will depend on the turnoverof storage bins 10 in presentation positions 116.

In a modified yet simplified form of the embodiment described withreference to FIGS. 8g and 8h the longitudinally extending rail or track313 carries a plurality of shuttle devices 310, the shuttle devices 310moveable along the track 313 along the base of the output columns 331,extending substantially parallel to the pick face 118. The shuttledevices 310 comprise a lift device and a bin receiving portion 132, thebin receiving portion 132 further comprising transferring means.

In use, a storage bin 10 is lowered by the load handling device 30 on tothe bin receiving portion 132. The shuttle device 310 is moved along thetrack 313 under the control of the computer control utility to the baseof the output column associated with the presentation portion 116requiring the storage bin 116 to be placed thereon. Once in position atthe base of the relevant output column 131, 331 the lift device isactivated so as to lift the storage bin 10 receiving portion 132 to thelevel of the predetermined presentation position 116. Once the storagebin 10 is at the required level within the output column 131, thetransferring means is activated so as to move the storage bin 10 fromthe bin receiving portion in to the presentation position 116 or thepre-pick storage position 126 or in to the additional storage position128.

It will be appreciated that the transferring means may be of anysuitable form to fulfil the function described and may be of the form ofany of the transferring mechanisms described above with reference to anyof the other embodiments of the invention or forms thereof.

It will be apparent to a person skilled in the art that there are manyways of achieving the above results and that any suitable mechanism forachieving the objective may be envisaged.

Advantageously, with reference to all the embodiments of FIGS. 7 and 8,in the case of a single shuttle device 310 or bin lift device 300malfunctioning there will be other shuttle devices 310 or bin liftdevices 300 in situ capable of taking over. Additionally, with referenceto the simplified embodiment described above, it may be possible for amalfunctioning shuttle device 310 to be pushed or pulled out of the wayby a functioning shuttle device 310. In this way, there is no singlepoint of failure in replenishing the presentation positions 116 in thepick face 118.

In an alternative form of this embodiment, storage locations 126 asdescribed with reference to the previous embodiments may be disposedbetween the bin lift device 300 and the presentation positions 116. Suchadditional storage positions 126 may be provided on one or both sides ofthe bin lift device 300.

Further forms of the invention are shown in FIGS. 9, 10 and 11. Itemsreferenced in the systems described above both in the preamble and thefirst and second embodiments of the invention will retain the samereference numerals. It will be appreciated that these forms of theinvention may be combined with any or all of the above embodiments andall alternatives referenced therein to provide maximum flexibility inlarge CFC operations in online retail environments.

FIG. 9 shows a further form of the invention comprising a pick aisle 100positioned within a grid-based storage area 102. In this form of theinvention, the storage area 102 comprises distinct areas 402 a and 402 beither side of the pick aisle 100.

The storage area 402 in all other respects, is as described in any ofthe above previously described embodiments.

The storage area 402 a comprises a storage area capable of pallet-sizedstorage. The load handling devices 400 are sized and configured so as tobe able to pick up, move and deposit pallets of predetermined andstandard sizes adjacent the pick aisle 100. Larger items or itemsdelivered to the CFC by suppliers in bulk and on pallets are storedwithin the specially configured grid-based system 402 a.

In use, items required at the pick stations 114 that are stored withinthe storage area 402 b are picked from the relevant presentationportions 116, having being delivered to the presentation positions 116in any of the ways described above.

In use, items stored in the pallet section of the storage area 402 a arehandled in a similar fashion to those in the storage area 402 b, withthe exception that there are no presentation portions 116. Items orproducts located on pallets are delivered directly to the pick aisle 100where an operative 120 on the opposite side of the pick station 114 canbreak down the pallet and pick items from the pallet in to temporarystorage areas (not shown) at the order assembly area 104. Such temporarylocations at pick stations are described in Patent No. GB 2,524,383 B1dated 5 Dec. 2016 (Ocado Innovation Limited) incorporated herein in itsentirety by reference.

Advantageously, use of a pallet-sized, grid-based storage system andstorage area 402 a enables items to be stored and accessed without alengthy decant process being required to break down items and productson pallets and put them in storage bins 10 and into the system 102.However, not all items are delivered on pallets so both systems arerequired and can advantageously be combined in the above manner.

FIG. 10 shows a further form of the invention comprising a pick aisle100 positioned within a grid-based storage area 102. In this form of theinvention, the storage area 102 comprises distinct areas 502, 502 a and502 b each distinct area comprising a separate area of grid-basedstorage system separated by dividers or crash barriers 504. In this formof the invention, the distinct areas 502, 502 a and 502 b comprisedifferently sized storage bins 10, 10 a and 10 b. With reference to FIG.10, the order picking system works in exactly the same manner asdescribed above with reference to the preceding embodiments. Thedifference is only that the presentation positions are sized so as toaccept storage bins 10 of different distinct sizes. It will beappreciated that in the example described herein, there are three sizesof storage bin 10, 10 a and 10 b. Storage bin 10 is a bin of similarsize to that described above; storage bin 10 b has a footprint with across-sectional area the size of an integer number of storage bins 10;and storage bin 10 b has the same footprint as the storage container 10but is taller. Again it will be appreciated that these are just some ofthe sizes of storage bins 10 that may be used but this form of inventionis not limited to these sizes.

A storage system of this form having multiple different sized roboticload handlers and storage bins 10 is described in GB Patent No GB2,528,573 B1 dated 8 Feb. 2017 (Ocado Innovation Limited) the contentsherein incorporated by reference in entirety.

In all other respects, the order picking system, and specifically thestorage area 502 within the order picking system operates insubstantially the same manner as that described above with reference tothe other embodiments of the invention.

FIG. 11 shows a further form of the invention in which multiple pickaisles 100 on different levels are serviced via a single grid-basedstorage system. Again, the order picking system operates in the samemanner as described with reference to the embodiments above, and mayinclude the alternatives and other examples described previously.

However, in order to enable the robotic load handlers 30 to depositstorage bins 10 on landing positions 132 on multiple levels it isnecessary to stagger the presentation positions 616 on the first levelwith respect to the presentation positions 616′ on the second level.

FIGS. 12 and 13 show further forms of the invention in which thegrid-based storage system is provided with a conveyor-based pick aisle100. In these forms of the invention, the grid-based storage system pickstations 714 are provided within the CFC environment.

With this in mind, FIG. 12 shows an order picking system where the zonepick area including the pick aisle 100 is disposed on one face of thegrid-based storage system.

The combination of the zone-pick, pick aisle 100 and the grid-basedstorage system 102 enables fast moving products and items to be handledin the zone pick area as described in detail above and the slower movingitems to be handled in order assembly areas at pick stations 714. At apick station 714 in accordance with one form of the invention, a storagebins 10 containing items required for a customer order and a deliverycontainer DT designated for the specific customer order are deposited atthe pick station 714. The item (or items) required from the storage bin10 is picked from the storage bin 10 in to the delivery container DT andthe storage bin 10 is retrieved by a load handling device 30 andreturned to a stack 12 in the storage area 102. The delivery containerDT may remain at the pick station 714 awaiting other items, until allitems required for the same customer order have been transferred in tothe delivery container DT from load handling device delivered storagebins 10.

The faster moving items handled in the manner described above withreference to the various embodiments of the invention are picked in todelivery containers DT at the zone pick aisles 100. The deliverycontainers DT may then be placed in storage bins 10 and input in to thestorage system as previously described above, the entire customer orderwhen assembled across a plurality of delivery containers DT may besequenced within the storage system for output in a single movement to adispatch area ready sorted for the required delivery route.

It will be appreciated that empty storage bins 10, or storage bins 10comprising delivery containers DT, or storage bins comprising deliverycontainers DT and bags 52, may all be stored within the stacks 12 withinthe storage area 102. Accordingly, suitable means for inputting suchcontainers or combinations thereof may be used as described above.Alternatively, other forms of input methods will be apparent to a personskilled in the art.

FIG. 13 shows a further arrangement of zone pick system with grid-basedsystem. In this form of the invention, the pick station 714 of thegrid-based system is disposed in the system adjacent a zone pick aisle.In this way, the faster moving items and products handled in the zonepick area may be merged with the slower moving items handled in thegrid-based pick stations. A single operative 120 may pick from bothareas. Alternatively a plurality of operatives may work in a singlepicking area to assemble a single customer order in a series of deliverycontainers DT at the pick station 714, the delivery containers DT beingstored in storage bins 10 and input in the storage system for sequencingand dispatch at the required time.

It will be appreciated that there may be a large number of storage bins10 in any given storage system and that many different items may bestored in the storage bins 10 in the stacks 12, each storage bin 10 maycontain different categories of inventory items within a single stack12.

It should be noted that the delivery container DT may be an actualdelivery container for onward transmission to the customer or be a binor container 10 with “post pick” items destined for delivery tosomewhere else, for instance to an alternative fulfilment centre. Theterm delivery container DT is used to distinguish storage bins 10 fromdelivery containers DT.

It will also be appreciated that the delivery container DT may becontained within a storage bin 10 when stored within the grid-basedsystem to ensure that the robotic load handling devices can handle themovement of all bins or containers whether in the stacks 12 of the mainstorage system or in a nominal robotic picking area.

Furthermore, the containers, bins or totes used in any of theabove-described embodiments of the invention and all forms andvariations thereof may be of a 180 degree “stacking and nesting”configuration in which rotation of two similar containers by 180 degreesrelative to one another changes the ability of the containers to stackor nest accordingly.

Additionally, the embodiments of the invention and all forms thereofhave been described based on the use of open-topped containers, bins ortotes. However, it will be appreciated that any suitable form ofcontainer, bin or tote may be used. For example containers, bins ortotes may be provided with lids (hinged or otherwise) side openingpanels or end opening panels or any other form suitable for thedescribed purpose.

Furthermore, it will be appreciated that the storage bins 10 need not beof the configuration shown in the appended Figures. The storage bins 10may be of rectangular footprint or of square footprint. Additionally,the storage bins 10 are shown in the presentation positions 116 with theshort edge leading, to increase the density of packing of the bins 10.However, a long-edge leading configuration is equally possible.

It will be appreciated that the load handling devices described abovemay be of the form described in detail in the specific embodiments andthe referenced drawings. However, any form of load handling device maybe used which may include but not be limited to load handling devicescomprising cavities, load handling devices of a cantileverconfiguration, shuttles, gantry cranes or any other form of loadhandling device suitable for the function described.

It will further be appreciated that whilst many of the above embodimentsare described with reference to a remote or separate robotic pickingarea, it is possible that the main storage system be used as a roboticpicking area at the same time as functioning as a conventional pickingand storage system.

In all the embodiments described above, picking of items from storagebins 10 in to delivery containers DT may be performed manually byoperatives or may be performed robotically by suitably controlledrobotic picking devices.

It will further be appreciated that the picking operation describedabove need not only apply to the picking of customer orders, the pickingoperation could be part picking of delivery containers DT or other formsof container, bin or tote for onward transmission to a smaller CFC in aCFC hierarchy, or as part of a supply or delivery network

Furthermore, whilst the above system is described with reference toorder picking within an online retail operation, specifically onlinegrocery retailing, it will be appreciated that the system may find usein other order picking systems. For example the picking of generalmerchandise items is envisaged. Furthermore, the systems described couldbe used in other manufacturing environments where large numbers of partsare required to be accessed regularly, for example in car or vehicleassembly lines.

1. A system for picking items from storage, the system comprising: agrid-based storage system, the storage system having a series of storagecontainers, the storage containers being configured to contain items tobe stored, the storage containers being located in stacks within aframework, in which a portion of the framework includes at least oneoutput column, the or each output column being configured and adapted toreceive at least one storage container moved from the storage system, atleast one of said output columns being provided with a plurality ofpresentation positions, the storage containers being configured to bemovable from storage positions within the stacks to said presentationpositions remote from the stacks via the or each output column, saidpresentation positions being arranged so as to locate a plurality ofstorage containers on at least one face of the storage system, thepresentation positions being arranged such that the items stored in saidstorage containers are accessible to an item picker.
 2. A system forpicking items according to claim 1, in which the system comprises: atleast one load handling device operative on rails or tracks, the railsor tracks being disposed on substantially horizontal members of theframework, the or each load handling device including: a liftingmechanism for engaging at least one storage container so as to lift saidstorage container from a stack, said load handling device furtherincluding: drive means for driving said load handling devices from afirst position above a stack of storage containers to a second positionabove an output column.
 3. A system according to claim 1 in which thesystem comprises: a plurality of output columns said output columnsdefining a plurality of associated presentation positions, thepresentation positions associated with said plurality of output columnstogether defining an array of presentation positions on at least oneface of the storage system.
 4. A system according to claim 3, in whichsaid output columns further comprise: transferring means fortransferring a load handling device delivered storage container to apresentation position associated with said output column.
 5. A systemaccording to claim 4, in which the transferring means comprises: a binlift device, said bin lift device being configured as movable within anoutput column between positions corresponding to presentation positions.6. A system according to claim 5, in which the bin lift devicecomprises: a storage bin receiving portion, said bin lift deviceincluding conveyor means configured to transfer a storage bin located onthe receiving portion to a predetermined presentation position withinthe array of presentation positions on one face of the storage system.7. A system according to claim 4, in which the transferring meanscomprises: a frame carrying at least one shuttle device, said framebeing disposed within the plurality of output columns.
 8. A systemaccording to claim 7, in which the frame comprises: tracks on which theor each shuttle device 310 is moveable, the or each shuttle device beingconfigured as moveable around the tracks to positions within the outputcolumns corresponding to presentation positions within the array ofpresentation positions on one face of the storage system.
 9. A systemaccording to claim 1 in which the at least one output column comprises:sensor means for detecting a presence of a storage bin in the outputcolumn, so as to prevent activation of the transferring means unless thestorage bin is located on the storage bin receiving portion.
 10. Asystem according to claim 3, in which the columns comprise: pre-pickpositions such that storage containers located in said pre-pickpositions will be transferred to said presentation positions by furthertransferring means on a storage container being removed from saidpresentation position, thereby replenishing the presentation positionwith a storage container as required.
 11. A system according to claim 4,in which the transferring means comprises: conveyor means.
 12. A systemaccording to claim 11 in which the conveyor means comprises: at leastone of a roller conveyor or belt conveyor.
 13. A system according toclaim 11, in which the conveyor means is a driven conveyor.
 14. A systemaccording to claim 4, in which the transferring means comprises: agravity fed conveyor mechanism.
 15. A system according to claim 14, inwhich the gravity fed conveyor mechanism comprises: a bin receivingportion, said bin receiving portion having a plurality of rotatablymounted rollers, said rollers being configured to transfer a storage binon the bin receiving portion on to an adjacent storage position withinan output column under a weight of a storage container when said binreceiving portion is rotated about a point on the at least one outputcolumn.
 16. A system according to claim 1, in which the item pickingsystem comprises: an order assembly portion.
 17. A system according toclaim 15, in which the order assembly portion comprises: conveyorsystems configured for carrying delivery containers in to which itemsare to be picked from the storage bins in the presentation positions.18. A system according to claim 15, in which the order assembly portioncomprises: trolleys carrying delivery containers in to which items areto be picked from the storage bins in the presentation positions.
 19. Asystem according to claim 15, in which a given array of presentationpositions is provided with an associated order assembly portion.
 20. Asystem according to claim 18, in which a plurality of order assemblyportions are associated with a given array of presentation positions.21. A system according to claim 19, in which the order assembly portionsare located across a number of levels of storage system.
 22. A systemaccording to claim 1 comprising: transferring means configured fortransferring storage containers removed from presentation positions tothe storage area via the transferring means acting on said storagecontainers so as to return the storage containers to the storage area.23. A system according to claim 1, configured such that storagecontainers removed from presentation positions will be placed to bemanually collected by an operative and returned to the storage area at alocation remote from the presentation positions.
 24. A system accordingto claim 1 in which the at least one output column comprises: stop meansconfigured and adapted so as to prevent movement of a storage bin from astorage position in an at least one output column to a presentationposition or from a storage position to a storage position within an atleast one output column.
 25. A system according to claim 24, in whichthe stop means comprises: a substantially L-shaped pivotally mountedmember mounted beneath a conveyor means in a bin receiving portion, suchthat a presence of a storage container on the bin receiving portion willact to pivot said substantially L-shaped pivotally mounted member suchthat a distal end of said L-shaped pivotally mounted member willprotrude through the bin receiving portion so as to prevent transfer ofa storage bin in to an adjacent position.
 26. A system according toclaim 2, in which the load handling device comprises: a cavity, thecavity being configured and adapted so as to receive a storage container10.
 27. A system according to claim 26, in which the load handlingdevice is configured to occupy a footprint of a single grid space in thegrid-based storage system.
 28. A system according to claim 2, in whichthe load handling device comprises: a cantilever-shaped body.
 29. Ansystem according to claim 1, configured for order picking, in which thestorage area of the grid-based storage system is configured and adaptedso as to store storage containers of multiple sizes.
 30. A systemaccording to claim 29, in which the storage system comprises:presentation positions arranged and adapted so as to present storagecontainers of sizes stored within the storage system.
 31. A systemaccording to claim 28, in which the storage area comprises: a grid-basedstorage system configured and adapted for storage containers containingpallets.
 32. A system according to claim 29, configured such that itemsto be picked may be picked from storage containers in presentationpositions or picked from order assembly areas associated with thegrid-based storage system, items in storage containers in presentationpositions having items designated as frequently picked items in acontext of an online retail system.
 33. A system according to claim 1 inwhich the system comprises: a computer control utility for controllingpositions and movements of storage containers within the system.
 34. Asystem according to claim 1, configured such that items to be picked arepicked from storage containers in to delivery containers robotically ormanually.
 35. A system according to claim 34, in which the deliverycontainers are stored within storage containers.
 36. A system accordingto claim 34, in which the storage area comprises: storage containerscontaining items to be picked and or delivery containers and or storagecontainers having delivery containers and or delivery containers havingpartially or fully picked customer orders.
 37. A method of picking itemsin an online retail system within an item picking system, the methodcomprising: picking items from a grid-based storage system having aseries of storage containers, the storage containers being configured tocontain items to be stored, the storage containers being located instacks within a framework, in which a portion of the framework includesat least one output column, the or each output column being configuredand adapted to receive at least one storage container-moved from thestorage system, at least one of said output columns being provided witha plurality of presentation positions; and prior to the picking, movingstorage containers from storage positions within the stacks to saidpresentation positions remote from the stacks via the or each outputcolumn, said presentation positions being arranged so as to locate aplurality of storage containers on at least one face of the storagesystem, the presentation positions-being arranged such that the itemsstored in said storage containers are accessible to an item picker.